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排序方式: 共有9185条查询结果,搜索用时 15 毫秒
21.
目的观察动物口服六味银杏胶囊的急性毒性和长期毒性反应。方法采用最大给药量法测定小鼠口服六味银杏胶囊的急性毒性;以20.0,10.0,5.0 g生药.kg-1.d-13个剂量的六味银杏胶囊(相当于临床用量68、34、17倍)灌胃SD大鼠,连续24周,观察服药24周及停药4周后,大鼠的生长发育、血液学、血液生化学、组织病理指标的变化。结果小鼠1天内口服六味银杏胶囊最大给药量为190.0 g生药/kg,相当于临床用量的700倍。长期毒性实验中,各剂量组与空白对照组比较,大鼠一般状况,体重增长,血液学、血液生化指标,主要脏器系数,肉眼观察及镜下组织形态学观察均无明显差异或异常。结论六味银杏胶囊临床用药范围内应用是比较安全的。 相似文献
22.
Lilan Jin Lu Deng Mark Bartlett Yiping Ren Jihong Lu Qian Chen Yixiao Pan Hai Wang Xiaokui Guo Chang Liu 《Nutrients》2022,14(10)
Air pollutants of PM2.5 can alter the composition of gut microbiota and lead to inflammation in the lung and gastrointestinal tract. The aim of this study was to evaluate the protective effect of a novel herbal extract blend, FC, composed of Lonicera japonica extract, Momordica grosvenori extract, and broccoli seed extract, on PM2.5-induced inflammation in the respiratory and intestinal tract. A549 cells and THP-1 cells, as well as C57BL/6 mice, were stimulated with PM2.5 to establish in vitro and in vivo exposure models. The models were treated with or without FC. The expression of inflammatory cytokines and tight junction proteins were studied. Proteomic analysis was performed to elucidate mechanisms. Mouse feces were collected for gut microbiota analysis. FC was shown to modulate the upregulation of pro-inflammatory cytokines mRNA expression in A549 and THP-1 cells and downregulated tight junction proteins mRNA expression in A549 cells due to PM2.5 stimulation. In animal models, the decreased expression of the anti-inflammatory factor il-10, tight junction protein ZO-1, and the elevated expression of COX-2 induced by PM2.5 were improved by FC intervention, which may be associated with zo-1 and cox-2 signaling pathways. In addition, FC was shown to improve the gut microbiota by increasing the abundance of beneficial bacteria. 相似文献
23.
星点设计-效应面法优化炒茺蔚子炮制工艺 总被引:1,自引:0,他引:1
目的:利用星点设计-效应面法对炒茺蔚子的炮制工艺进行优化,为炒茺蔚子的规范化生产提供依据。方法:采用清炒法,以炮制温度、炮制时间、炒药机转速为自变量,总生物碱、盐酸水苏碱、水溶性浸出物、醇溶性浸出物质量分数为评价指标,对自变量各水平进行多元回归拟合,利用效应面法筛选最佳炮制工艺并进行预测分析。采用UV测定总生物碱的含量,检测波长520 nm;采用高效液相色谱仪-蒸发光散射法测定盐酸水苏碱的含量,流动相乙腈-水(60∶40),流速0.5 m L·min~(-1),漂移管温度70℃。结果:三项式拟合复合相关系数较高。最佳炮制工艺为炮制温度219℃,炮制时间2 min,炒药机转速14 r·min~(-1)。总生物碱、盐酸水苏碱、水溶性浸出物、醇溶性浸出物质量分数的平均值分别为9.82,2.50,86.16,193.28 mg·g~(-1),综合评分与三项式拟合方程预测值偏差0.87%。结论:利用星点设计-效应面法优化炒茺蔚子炮制工艺的方法简便且预测性良好,适用于炒茺蔚子的规范化生产。 相似文献
24.
目的:观察银杏叶提取物对白介素-1β损伤的关节软骨细胞的作用及对细胞内一氧化氮体系的影响。方法:在无菌环境下消化得到3月龄雌性新西兰白兔膝关节软骨细胞,实验用细胞为第2代软骨细胞。软骨细胞与IL-1β(5μg/L)、IL-1β(5μg/L)+地塞米松(10-7、10-6、10-5mmol/L)、IL-1β(5μg/L)+银杏叶提取物(40mg、80mg、160mg/L)共同孵育,分别在72h后MTT法检测软骨细胞的增殖受到的影响;24h后测定受损伤软骨细胞培养液中的NOi、NOS,逆转录扩增(RT-PCR)检测iNOSmRNA。结果:MTT法显示IL-1β对软骨细胞的增殖有明显的抑制作用;地塞米松同银杏叶提取物均有对抗IL-1β的效应;地塞米松和EGb均能显著减少iNOSmRNAi、NOS、NO的生成(P<0.01);EGb761的这种效应有剂量依赖性。结论:银杏叶提取物通过抑制软骨细胞内的NO生成以保护IL-1β损伤的膝关节软骨细胞。 相似文献
25.
Ravi A Mallika A Sama V Begum AS Khan RS Reddy BM 《Journal of ethnopharmacology》2011,137(3):1353-1359
Ethnopharmacological relevance
The bark of Tecomella undulata is primarily used in the treatment of syphilis, painful swellings and cancer by traditional healers. Also, it is claimed to be useful in treating urinary discharges, enlargement of spleen, leucorrhoea, leukoderma, tumors, liver disorders, gonorrhea, gout and promotes wound healing in Indian traditional system of medicine.Aim
To establish a scientific validation for the antitumor effects of Tecomella undulata bark and explore the mechanistic pathway in chronic myeloid leukemia cell line, K562. The study was further extended to standardize the extract using quercetin as biomarker.Methods
Induction of apoptosis by chloroform extract of Tecomella undulata bark (CTUB) was determined by MTT, Annexin V and caspase activation assays. The cell cycle analysis was done by flow cytometer and nuclear staining by DAPI. The standardization of the extract was performed through reverse phase-HPLC method under PDA detection.Result
Results clearly showed the induction of apoptosis by CTUB in K562 cells. The effect was found to be dose dependent, having IC50 of 30 μg/ml with activation of FAS, FADD, caspase 8, caspase 3/7 and fragmentation of DNA. The bioactive CTUB was determined to possess 0.03% (w/w) of quercetin.Conclusion
The investigation clearly demonstrated the potential antitumor effect of CTUB, thereby validating the traditional claim. Quercetin, known to have anticancer activity is being reported and quantified for the first time from the bark of Tecomella undulata. 相似文献26.
27.
Konrath EL Neves BM Lunardi PS Passos Cdos S Simões-Pires A Ortega MG Gonçalves CA Cabrera JL Moreira JC Henriques AT 《Journal of ethnopharmacology》2012,139(1):58-67
Ethnopharmacological relevance
The study was aimed at evaluating medicinal and therapeutic potentials of two Lycopodiaceae species, Lycopodium clavatum (L.) and Lycopodium thyoides (Humb. & Bonpl. ex Willd), both used in South American folk medicine for central nervous system conditions. Alkaloid extracts were evaluated for chemical characterization, acetylcholinesterase and antioxidant activities.Materials and methods
The alkaloid extracts obtained by alkaline extraction were determined for each species by GC/MS examination. The evaluation of the anticholinesterase and the antioxidant activities of the extracts were tested by determining in vitro and ex vivo models. Effects on acetylcholinesterase (AChE) were tested in vitro using rat brain homogenates and ex vivo after a single administration (25, 10 and 1 mg/kg i.p.) of the alkaloid extracts in mice. The in vitro antioxidant effects were tested for the 2-deoxyribose degradation, nitric oxide (NO) interaction, 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity and total reactive antioxidant potential (TRAP). After an acute administration (25 and 10 mg/kg i.p.) of the extracts in middle-aged (12 months) mice, the antioxidant effects were estimated through the thiobarbituric acid reactive substances test (TBARS), and the antioxidant enzymes activities for catalase (CAT) and superoxide dismutase (SOD) were measured.Results
AChE activity was inhibited in vitro by the alkaloid-enriched extracts of both Lycopodium species in a dose and time-dependent manner in rat cortex, striatum and hippocampus. A significant inhibition was also observed in areas of the brain after acute administration of extracts, as well as decreased lipid peroxidation and increased CAT activity in the cortex, hippocampus and cerebellum. A moderate antioxidant activity was observed in vitro for the extracts. Chemically, the main alkaloids found for the two species were lycopodine and acetyldihidrolycopodine.Conclusion
This study showed that the biological properties of the folk medicinal plants Lycopodium clavatum and Lycopodium thyoides include AChE inhibitory activity and antioxidant effects, two possible mechanisms of action in Alzheimer's related processes. 相似文献28.
29.
介绍陈以平教授应用膏方治疗慢性肾脏疾病的经验。其临床辨证具有辨证与辨病结合、主证与次证兼顾、治病与防病并举的特点。用药强调治脾是关键,治肾是根本;清化之剂,贯穿始终;遣方用药,善用药对;中西合参,相得益彰。 相似文献
30.
Qing-Feng Liu Xiao-Jin ShiZhong-Dong Li Ming-kang ZhongZheng Jiao Bin Wang 《Journal of ethnopharmacology》2014